WASHINGTON— The Center for Biological Diversity warned Secretary of State Rex Tillerson today to produce the overdue U.S. Climate Action Report or face a lawsuit. The deadline to submit the report to the United Nations Framework Convention on Climate Change Secretariat passed on Jan. 1.

The Center’s letter notes that the State Department’s failure to submit the report by the deadline constitutes a violation of both the UN treaty and the federal Administrative Procedure Act.

“The U.S. is the chief culprit in the climate crisis, so its refusal to meet even bare minimum reporting requirements is morally reprehensible,” said Jean Su, associate conservation director at the Center. “In light of all the American lives and homes lost to superstorms and wildfires last year, the Trump administration’s inaction is especially disturbing.”

The objective of the UN Framework Convention on Climate Change is to stabilize greenhouse gas concentrations in the atmosphere to a level that prevents the most dangerous effects of climate change. The U.S. and other parties to the treaty must periodically submit reports on their greenhouse gas emission inventories and action plans consistent with this objective.

While tardiness in submitting the report has occurred, the U.S.’s complete failure to issue the report would be unprecedented. There is no indication that the months-long production process has even begun. Under past administrations the launch of this process was typically announced in the Federal Register up to eight months before the deadline; most previous report drafts were also made available for public review.

The United States is the largest cumulative emitter of greenhouse gases and the world’s second highest emitter on an annual and per capita basis, behind only China. China has come under scrutiny, including from the United States, for failing to submit its own report due last year.

The majority of the other parties to the convention have submitted their reports, including the European Union, Germany and Russia. Trump’s intention to withdraw from the Paris Agreement does not in any way affect U.S. legal obligations under the convention.

“Trump’s reckless decision to pull out of the Paris accord already made the U.S. a climate pariah,” Su said. “Further eroding the world’s trust could shatter the global, unified front the climate emergency demands. If Tillerson continues to blow off this bedrock commitment to transparency, we will take him to court.”

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 1.6 million members and online activists dedicated to the protection of endangered species and wild places.